Mark your calendars: The 2013 Outside Lands Music and Arts Festival is set for Aug. 9-11.

The dates for the mammoth three-day event, held annually at San Francisco's Golden Gate Park, were announced Tuesday. No other information was given. Keep checking the festival's website, www.sfoutsidelands.com, for updates.

Now comes the fun part: Trying to guess the three main-stage headliners for this year's event. Green Day? Black Sabbath? Red Hot Chili Peppers? Who knows? Whichever acts make the cut, however, will most likely be good ones. That's always the case with Outside Lands, which has presented such big-name headliners as Phish, the Dave Matthews Band, Tom Petty and the Heartbreakers, Arcade Fire and Radiohead over the years.

The 2012 event, which took place Aug. 10-12, featured an impressive trio of main-stage headliners -- Neil Young and Crazy Horse, Metallica and Stevie Wonder. It also, as per usual, featured dozens of other worthy acts, including Sigur Ros, Santigold, Of Monsters and Men, Alabama Shakes and Skrillex.